The cured resins obtained by combining cyanate esters with phenol compounds showed much lower dielectric constant (Dk) and dissipation factor (Df) than those of the conventional cured resins. It was concluded that this characteristics are due to their unique resin structures, in which the phenol compounds are incorporated in the triazine structures during the curing to form a loose cross-linking structure. Consequently the reaction rate of the cyanato group will increase and the quantity of unreacted cyanato groups remaining within the cured resin will decrease. More modifying effect was obtained by the phenol compounds with the electron-donor functional group, which are weak in acidity. As a result, it was realized that the lower cross-linking density of the cured resin by modifying the network structure with some compounds is effective in decreasing dielectric constant (Dk) and dissipation factor (Df).

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An adsorbent having a triethylammonium or pyridinium group was obtained as spherical resin beads from wasted packages of foamed polystyrene by chemical treatment.
The spherical Resins (Cr-PS) were prepared by treating polystyrene in a 1, 2-dichroloethane solution with 1, 4-dimehty1-2, 5-dichloromethylbenzene using antimony pentachloride as a Friedel-Crafts agent in a silicone dispersion medium. The crosslinked spherical resins obtained were useful and suitable as an adsorbent because of having adequate mechanical strengths and particle sizes. The particle size and yield of spherical resins were controllable with the synthetic conditions such as temperature, polystyrene concentration, rotation speed of stirrer, and so on. A cationic adsorbent having a triethylammonium (Cr-PCS-TEA) or pyridinium (Cr-PCS-Py) group was prepared by chloromethylation and the following reaction with triethylamine or pyridine. The introduction of functional group by chloromethylation could be attained at the degree of almost 100% to each benzene ring existing in the spheric resins. The amount of the triethylammonium group in Cr-PCS-TEA was 2.3meq/g-resin, and the pyridinium group in Cr-PCS-Py 3.5meq/g-resin. The adsorption ability of these cationic adsorbents for synthetic dyes (AcidRed18 and AcidYellow23) was investigated by a batch and a columnar method. Cr-PCS-TEA and Cr-PCS-Py could highly adsorb AcidRed 18 and AcidYellow23 over the anion exchange capacity of the resins, and the adsorbed dyes were recoverable with NaOH solutions.

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In this paper, chitosan membranes cross-linked with diethyleneglycol diglycidylether (DEDGE) and glutaraldehyde (GA) for the recycle of water in urine were prepared. The characteristics of permeation and separation for an aqueous solution containing urine components through their cross-linked membranes in pervaporation were examined. The obtained cross-linked chitosan membranes permeated water more preferentially than NH₄⁺ion. The DEDGE-cross-linked chitosan membranes showed higher water-permselectivity than the GA-cross-linked chitosan ones. Furthermore, pervaporation characteristics of these membranes are also discussed in detail from the viewpoint of membrane structures.

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New Polymers having hemiacetal ester structures in the main chain were synthesized by the polyaddition of dicarboxylic acids with divinyl ethers in a good yield. The polymers thus obtained gave a variety of mechanical properties and good solubility in organic solvents, as well as good compatibility with various other resins. Further, the thermosetting resins from these polymers, with which epoxy resins were compounded, formed cured tough films in the presence of a Lewis acid catalyst, and were found to be stable under the storage conditions (40°C×30days). They may serve as a novel polymer type latent hardener and be usable as a network polymer in the application fields, such as coatings, ink, adhesives, and underfill materials

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